Dissident Vietnamese poet Nguyen Chi Thien, who memorized his poems while languishing in prison where he was not allowed to write, has died at age 73.

A friend of Thien announced his death this week in Los Angeles, where he had lived since 1995.

Thein was first jailed in 1960 after telling a group of Vietnamese students that World War II ended when the United States dropped atomic bombs on Japan. Official communist-issued textbooks insisted that the war ended by the Russians defeating the Japanese.

Thien spent most of the next 31 years in jails and prison camps, where he memorized his poems and only writing them down after he was released.

His collection, Flowers of Hell won him international awards and honors.

Thien moved to France and later to the United States, where the Vietnamese community in Southern California saw him as a symbol of freedom.